The equational theory of union-free algebras of relations
Let \(\mathcal P\), \(\mathcal R\) be the classes of algebras isomorphic to positive, subpositive (no \(\cap\)) set relation algebras, respectively. The authors show that the equational theories of \(\mathcal P\), \(\mathcal R\) are decidable and that \(\mathcal R\) is not a variety.
scientific article; zbMATH DE number 780795
scientific article